Mechanical connecting device

ABSTRACT

A projector lamp includes a housing rear wall with a central opening and a coaxial disc having a central opening surrounded by a truncated conical lip bearing on the rear wall. A lamp socket forward of the disc includes an axial screw projecting loosely through a sleeve fixed to the disc and engaged by a thumb nut. A pair of screws project through 90* spaced holes in the rear wall and engage tapped openings in the disc. A spring member includes a rear annulus bearing on the disc front face and curved, forwardly directed, angularly spaced leaf springs engaging peripherally spaced points on the socket and a leaf spring engaging the housing wall to rearwardly urge the spring member. The lamp socket is universally adjustable by the pair of screws and thumb nut.

United States Patent [191 Arai Related U.S. Application Data [62] Division of Ser. No. 275,030, July 25, 1972, Pat. No.

[30] Foreign Application Priority Data Aug. 5, l97l Japan ..46700 l 6 [52] U.S. Cl. 240/41 L; 240/41 R; 240/413; 240/52 240/81 [5]] Int. Cl. F2lm 13/04 [58] Field of Search 249/41 BM, 4| SC, 4i L, 240/4l R, 52 R, 52.], Si

[56} References Cited UNITED STATES PATENTS Bausch 240/4l R Douglas 240/4! R Douglas 240/4l R ll/l907 3/1938 3/1938 51 May 27,1975

Primary ExaminerRichard M. Sheer Attorney, Agent, or FirmWolder & Gross [57] ABSTRACT A projector lamp includes a housing rear wall with a central opening and a coaxial disc having a central opening surrounded by a truncated conical lip bearing on the rear wall. A lamp socket forward of the disc includes an axial screw projecting loosely through a sleeve fixed to the disc and engaged by a thumb nut. A pair of screws project through 90 spaced holes in the rear wall and engage tapped openings in the disc. A spring member includes a rear annulus bearing on the disc front face and curved, forwardly directed, angularly spaced leaf springs engaging peripherally spaced points on the socket and a leaf spring engaging the housing wall to rearwardly urge the spring member. The lamp socket is universally adjustable by the pair of screws and thumb nut.

6 Claims, 6 Drawing Figures MECHANICAL CONNECTING DEVICE REFERENCE TO CO-PENDING APPLICATIONS The present application is a divisional application of co-pending Patent Application Ser. No. 275,030, filed July 25, I972 now U.S. Pat. No. 3,832,075 granted Aug. 27, 1974.

BACKGROUND OF THE INVENTION The present invention relates generally to improvements in mechanical connectors and projector lamps. and it relates particularly to an improved separable coupling and a projector lamp adjusting mechanism.

It is frequently desirable to interconnect the components of various devices by coupling means which permits the rapid firm assembly and disassembly ofa pair of components without the use of tools. Among the devices frequently requiring such separable coupling means are for example, toys, lighting fixtures, various appliances and the like. The separable coupling means heretofore available or proposed possess numerous drawbacks and disadvantages. They are generally awkward arrangements of low reliability and often complicated and expensive, of little versatility and otherwise leave much to be desired.

SUMMARY OF THE INVENTION It is a principal object of the present invention to provide an improved projector lamp and mechanical connecting device.

Another object of the present invention is to provide an improved separable coupling.

Still another object of the present invention is to provide an improved mechanical separable coupling which may be easily operated without the use of tools.

A further object of the present invention is to provide an improved light projector having a lamp position adjusting mechanism for selectively varying the light projecting and focussing characteristics of the projector.

Still a further object of the present invention is to provide a separable coupling and adjusting mechanism of the above nature characterized by their reliability, simplicity, ruggedness, ease of operation, low cost and great versatility.

The above and other objects of the present invention will become apparent from a reading of the following description taken in conjunction with the accompanying drawings which illustrate preferred embodiments thereof.

In a sense the present invention contemplates the provision of a separable coupling comprising a female coupling member including a first peripheral wall having a plurality of circumferentially spaced recesses accessible at the inner face of the peripheral wall and cam defining faces tapered radially outwardly in a direction from each of the recesses toward the outer edge of the wall, a male coupling member having a circular second peripheral wall at least partially telescoping the first peripheral wall and having peripherally spaced openings registering with corresponding recesses, and an elongated resilient member disposed in the male coupling member and having outwardly directed ears resiliently biased outwardly under the influence of the resilient member through respective of the openings and into engagement with the recesses when the coupling members are in coupled condition.

The peripheral walls ofthe coupling members may be of conical or cylindrical shape and continuous or interrupted along their circumferences. The recesses and openings are advantageously circumferential slots and the locking member is formed of spring wire with the ears having outwardly converging sides. Cam faces are formed on the inside surfaces of the female coupling member peripheral wall, the cam faces flaring outwardly toward the wall outer edge. In the fully extended condition of the ears. the distance of the ends of the cars from the center of coupling member is less than that of the outer edges of the cam faces. Where the peripheral walls are conical the inside surface of the female coupling member defines the cam faces.

Another feature of the present invention resides in the lamp position adjusting mechanism in the light projector in which an adjusting plate is positioned in front of the projector rear wall and carries an axial sleeve projecting rearwardly through an opening in the projector rear wall. A conical lip projects rearwardly from the adjusting plate around the sleeve and bears on the projector rear wall and a pair of spaced adjusting screws extend through openings in the projector rear wall and engaged tapped openings in the adjusting I plate. A spring member includes an annulus bearing on the adjusting plate front face, radially extending forwardly projecting curved leaf springs supporting a lamp socket at their free ends and a leaf spring engaging a fixed point to rearwardly urge the annulus. A screw projects rearwardly from the lamp socket through the sleeve and is engaged by a thumb nut at its rear portion.

The improved coupling and lamp adjusting mechanism are reliable, simple, rugged, highly reliable and of great versatility.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a front perspective view of a coupling embodying the present invention illustrated in a separated condition;

FIG. 2 is a view similar to FIG. I of another embodiment of the present invention;

FIG. 3 is a fragmentary longitudinal sectional view of still another embodiment of the present invention shown in which the coupling is shown in a coupled condition;

FIG. 4 is a bottom perspective view, partially broken away, of a further embodiment of the present invention shown in a separated condition;

FIG. 5 is a longitudinal sectional view of an adjustable lamp employing the coupling of the present invention; and

FIG. 6 is an exploded perspective view of a part thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 which shows a preferred embodi ment of the present invention for separably coupling two separate male and female coupling member which respectively include cylinders l and 2 by mating or telescoping the first cylinder 1 within the second cylinder 2 which has a relatively large wall thickness and an inner diameter equal to the outer diameter of the first cylinder 1. Within the cylinder I is positioned a spring 3a in a transverse plane perpendicular to the longitudinal axis of the cylinder 1 in such a manner that it resiliently presses on the inner wall surface of the cylinder l. The spring 3a is a wire spring having the configuration of expandable arch. The spring 30 has looped or bent sections or ears 3a with outwardly converging sides and which project outwardly from both ends of the spring 30 and at any convenient positions therebetween. The ears 30' pass through corresponding holes 4 in the shape of slots formed in the wall of the first cylinder and the projecting end of each ear or looped sections extend outwardly to some extent from the circumferential surface of the first cylinder 1. Moreover, there are formed tapered surfaces in the inner wall surface of the thick-walled cylinder 2 at positions where the projecting outer end portions of the looped sections or ears 3a engage the second cylinder 2 during coupling. As the cylinder 1 is inserted in the cylinder 2 to an increasingly deeper position, the tapered surfaces 5 cooperate with the outwardly projected portions of the looped sections and push them into the associating holes 4 formed in the cylinder 1. In the wall of the cylinder 2, there are formed slot shaped holes or cavities 6 at the positions adjacent to the inner edge of the ta pered surfaces.

The outwardly projecting portions of the cars 30' formed on the expandable spring 3a are pushed into the wall of the cylinder 1 by means of the tapered surfaces 5 on the cylinder 2 as the lower end of the cylinder 1 is inserted in the cylinder 2 to an increasingly deeper position against the outward bias of spring 3av When the outwardly projected ends of the ears pass over the inner edge of the tapered surfaces 5 and reach the positions opposite to the through holes or cavities 6 formed in the wall of the cylinder 2, the outwardly projected ends of the looped sections are allowed to enter the through holes or cavities 6 by the expanding force of the spring 3a. Thus the mating cylinders l and 2 are firmly coupled togetherv When it is desired to separate these two cylinders from each other, one of the cylinders is rotated with respect to the other about their common axis. The engaging portions of the loop sections or ears 30 formed on the spring 30 will then be pushed into the wall of the cylinder 1 against the expanding force of the spring 30 due to the sliding contact with the edge of the through holes or cavities 6, so that these mating cylinders can be pulled away in the opposite directions along the common central axis. Upon separation of these cylinders, the spring 3a restores to the initial position as shown in FIG. 1 due to the ex pandability of the spring 3a.

In FIG. 2 there is illustrated another embodiment of the present invention. wherein the outer cylinder is formed of thin plate. In this embodiment. there are formed in the enlarged upper border 2a of the female coupling member outwardly bulging bill-shaped sections 5a having cam-defining tapered inner surfaces. Also formed in border are holes 6a at positions adjacent to the inner edge of the tapered surfaces. These tapered surfaces and holes 60 are essentially equivalent to the tapered surfaces 5 formed internally in the thick wall of the cylinder 2 and to the through holes or cavities 6 as shown in FIG. 1. In FIG. 2, the expandable arched spring is positioned in cylinder in and is shown as a V-shaped expandable spring 319 having ears or looped sections 3b at both ends thereof. It will be noted that the expandabie spring may include additional ears looped sections other than those formed at both ends thereof.

FIG. 3 shows still another embodiment of the present invention in which the coupling members 1c and 2c are of conical shape. In this case since the conical inner surface of the external cylinder 2c serves to push the looped sections 30' of the expandable spring 3c into the wall of inner cylinder lc at the early stage of mating of the two cylinders, there is no need of forming tapered surfaces as described previously in connection with FIGS. 1 and 2 for pushing the ears looped sections inwardly. The inside face of the upper border of female member 2(- defines cam faces.

FIG. 4 shows a further embodiment according to the present invention adapted to detachably couple, for example. a dishlike decorative metal cap 7 mounted on top of a hanging pipe of a pendent type lighting fixture with a mounting plate 8 fixedly attached to the ceiling board 9 by means of rivets or the like. The circumferential wall of the dish-like decorative metal cap 7 is shaped conically, and the mounting plate securedly mounted on the ceiling board includes a disk having three integral lugs 8a depending from the periphery thereof. The lugs 8a are so designed that they correspond to a portion of the circumferential wall of a virtual hollow cone which may be established with the mounting plate 8 as its base. The dimensions of the lugs 8a are such that, when the decorative metal cap 7 is mounted coaxially over the mounting plate 8, the lugs 8a can be brought into contact with the inner surface of the conical circumferential wall of the metal cap 7. In each lug 8a there is formed a horizontal slot adapted to receive a corresponding ear or bent loop section of the expandable arched spring 3d in the same manner as described in the previous embodiments. Thus the projected or outer end portions 3d of the looped sections will slightly extend beyond the lugs. In the conical circumferential wall of the dish-like decorative metal cap 7 are formed horizontal slots 6a, which are adapted to receive the projected end portions of the looped sections when the open end surface of the dish-like decorative metal cap 7 is brought into contact with the ceiling board. It will readily be understood from the above description that the coupling means shown in FIG. 4 substantially corresponds in construction to the embodiment of FIG. 3. Thus in FIG. 4 when the dish-like metal cap 7 is mounted coaxially over the mounting plate 8 secured on the ceiling board, the projected end portions 3d of the ears or looped sections formed on the spring 3d will enter the corresponding slots 6d formed in the conical circumferential wall of the dishlike metal cap so that the latter can be mounted on the ceiling. It will be understood that the cap 7 en be dismounted from the ceiling board by rotating the same around the central axis thereof.

Although the embodiment of FIG. 4 has been de scribed as a coupling means for mounting a decorative metal cap of a pendent type lighting fixture onto the ceiling board, the structure may be inverted to make a coupling for detachably mounting the dish-like metal cap 7 which is coaxially secured at the bottom of the post 70 onto the floor board by use of a mounting plate having lugs. Of course the conical mating members shown in FIG. 4 may also be made to have right cylindrical configurations as shown in FIG. I or 2.

It is known that the mating cylindrical bodies can be held together by means of some knock pins or balls. In such a conventional arrangement, the individual knock pin or ball has to be arranged resiliently in the wall of the cylindrical bodies. This arrangement. therefore. is hardly applicable to the hollow bodies having a small wall thickness, and also the structure of the resulting coupling means becomes disadvantageriusly compli cated. According to the present invention, in place of the knock pins or balls, looped sections or ears are formed on an expandable spring which is extended along the inner surface of one mating cylinder. This ar rangement is advantageous especially when some components are to be accommodated within the cylinders. because this arrangement minimally decreases the internal space within the cylinders.

In FIGS. 5 and 6 there is shown a lamp adjusting mechanism and a coupling according to an embodiment of this invention in a projector for illuminating a room. stage or display goods. The left half portion 101 defining an outer cylindrical body is open at its rear end (in this description, the left and right ends of the illustrated projector correspond to the rear and front ends thereof respectively). An end plate 101a having a CCU tral light-transmitting opening 102 formed therein is suitably secured in position to the inner front border of the half portion 101. On the end plate 1010 are positioned four stay bolts 103 at locations corresponding to the corners of a square the center of which coincides with the center of the end plate. A front end plate of the inner cylinder 104 is arranged coaxially with, but spaced from the half portion 101 of the outer cylinder by means of spacer tubes mounted on the stay bolts 103. The front end plate ofthe inner cylinder has a central light-transmitting opening drilled therein, which is approximately equal to the light-transmitting opening 102 in size and configuration. To the open rear end of the inner cylinder is riveted the peripheral flange of the rear inner cylinder 106 with the circumferential collar of a concave reflecting mirror 105 being sandwiched therebetween. In the rear end plate 106:: of the rear inner cylinder 106 and in the reflecting mirror are formed. respectively, central openings for permitting a light source lamp 107 described hereunder to be inserted from the rear side along the main optical axis of the projector.

To the front extensions ofthe four stay bolts 103 and spaced from front end plate 101a by spacer tubes mounted around the stay bolts is fastened with associated nuts the rear end flange of a cylinder 109 for slideably guiding a lens holding sleeve 108. Since a headed screw 110 screwed into the lens holding sleeve 108 which is inserted in the guide cylinder 109 is slideable along the axially extending slot 109a formed in the guide cylinder 109, the lens holding sleeve 108 and the guide cylinder 109 can be locked together at any desired relative position along the common axis thereof.

Between the front end plate 101a of the outer cylinder 1 and the rear end of the cylinder 109 for guiding the lens holding sleeve 108 extend a pair of leaf springs 123 at both sides of the light-transmitting opening 102. If desired, for adjusting the light to be projected a mask plate 112 having a central opening 111 may be secured between the leaf spring 123 and the front surface of the end plate 101a. The outer cylinder 113 shown in the right portion of FIG. 5 is releasably mounted around the outer peripheral surface of the bent portion formed on the front end plate 101a so that the rear and front outer cylinders 101 and 113 form a detachably coupled single cylindrical body having a common axis, by means of a releasable coupling of the construction shown in FIG. 3. in which the front end section ofportion 101 is conical and nests in the conical end section of portion 113. and the looped sections 3(" of a curved wire spring located in portion 101 project through slots in portion 101 and releasably engage aligned slots in portion 113. The rear outer cylinder 101 is kept in association with a suitable base (not shown) by means of some universal joint so that the axis of light to be pro jected can be directed in any desired direction and. if desired, said universal joint can be locked once the di' rection of the light being projected has been decided.

On the rear end portion of the inner cylinder 106 is disengageably mounted a cup-shaped body 114 at its open peripheral edge, the cup-shaped body 114 being adapted to hold therein a light source lamp. A discshaped metallic washer 115 is coaxially arranged on the rear end of a socket 1070 (see FIG. 6) adapted to re ceive the light source lamp 107 and. by riveting the washer 115 with the bent end portions of the metallic strip 116 attached on the socket, the washer 115 and the socket 1070 are coupled together and form an integral unit. Additionally, a screw 118 is inserted in the central hole drilled in the washer 115 from the right hand side in the plane of FIG. 6. At a time when the counter-sunk head of the screw 113 is received in the counter sink of the central hole, the circumferential area and the counter-sunk head of the screw 118 are soldered together so that the screw 118 forms an integral extension of the axis of the socket 107a. The screw 118 also extends loosely through the central hole formed in a ring 119 formed of a phosphor bronze plate. The ring 119 has several integral leaf springs 119a extending outwardly in various directions from the ring 119. These leaf springs 119a are all curved towards the washer 115 in such a manner that each end thereof can be inserted in and secured by an associated slot 115a in the washer 115. The peripheral notches 115b, which are formed in the washer 115 at positions adjacent to respective slots 1150, provide the leaf springs 119a with clearances when the leaf springs 11% are bent sufficiently as shown in FIG. 5. One or more of the leaf springs 119a are shaped to have a gentler curve than the other leaf springs 119a as shown at 119b. By engaging a notch 119b' formed on the free end of leaf spring 1191) with a projection 114a formed on the inner wall surface on the cupshaped body 114 at a suitable position, the springs 119a press the ring 119 towards the bottom of the cup-shaped body 114. A disc 120 is arranged coaxially between the ring 119 and the bottom plate of the cup-shaped body 114. At the center of the disc 120 is formed a cone-shaped counter sink 120a of which circumferential surface is soldered with the outer peripheral surface of the inner end (right end as seen in the drawing) of a bushing 12011 inserted in the central sink 120a from the left hand side as seen in FIG. 6, so that the bushing 1201) and the disc 120 form substantially an integral unit. The bushing 120!) extends loosely through the central hole formed in the bottom plate of the cup-shaped body 114 as shown in FIG. 5. Within the bushing 120b is loosely inserted the screw 118 and on the leading end of the screw 118 is mounted an adjusting nut 121. A pair of holes are drilled in the bottom of the cup-shaped body 114 at an equal distance from the center of the bottom of the cup-shaped body along the two radii which intersect each other at right angles. There are in sertcd in these holes a pair of headed screws 122 from the left hand side as seen in Fl(i. 5, the leading ends of the screws [22 being screwed in the corresponding cccentric threaded holes 1220 formed in the disc I20. These two eccentric threaded holes 122a. also. are loeatcd along two radii which intersect each other at right angles at the center of the disc 120. ()n the peripher he disc 12" are formed notches I2llr. which provide the leaf springs 1190 with clearances as in the same manner as the notches 115/ formed in the washer 115 and serve to prevent the relative rotation between the ring II) and the disc l2".

As the structure for supporting the light source lam within the cupshaped body 114 is as above. the light source lamp 107. socket 107a. washer 115. and screw 118 form substantially a single integral body which is biased rightwards in the plane of FIG. by the resilient force of the leaf springs 119a. On the other hand. the truncated cone formed on the disc 120 which is integrally connected with the bushing 120i) is pressed by leaf springs [19b against the inner surface of the bottom plate ofthe cup-shaped body 114. Therefore. if nut 12! shown in the left end portion of HG. S is screwed in, the light source lamp 107 will be retreated along the main optical axis against the forward biasing force of the leaf springs 11911. On the contrary, if the nut is screwed out. the light source lamp 107 will be advanced by the biasing force of the leaf springs 119a. In addition. when either one of the two screws 122 of which heads are exposed outside the bottom plate of the cup-shaped body 114 is tightened. the screw H8 which is coupled integrally with the light source lamp will be tilted about the truncated cone formed on the disc [20 towards the screw 122 which has been tigltt ened. As mentioned above. each ofthe two screws 122 is disposed on either one of the two radii which intersect each other at right angles at the center of the base plate on the cup-shaped body 114, the light source lamp can be tilted, by tightening or loosening either one ofthe screws 122, in both the vertical and horizontal planes and furthermore. by appropriately tightening or loosening both the screws 122, to any intermediate directions between the vertical and horizontal planes.

The lamp assembly is mounted to a female coupling member 137, of similar construction to that shown in FIG. 4, by means of a post 137a coaxial with coupling member 137 and having one end secured to the hori Zontal plate of coupling member [37 and its other end suitably connected to the forward border of shell I0]. Like the female coupling member shown in FIGv 4. the coupling member includes a conical peripheral wall which is beaded along its edge as at 138 and has formed therein a plurality ofcircumferentially spaced horizon tal slots 133d corresponding to slots 61/. in other respects the coupling member 137 is similar to that shown in FIG 4 and may be employed with a mating male coupling member, like that shown in FIG. 4. which is provided with an associated wire spring having outwardly directed cars. or like that shown in FIG. 3.

While there have been described and illustrated preferred embodiments of the present invention. it is upparcnt that numerous alterations. omissions and additions may be made without departing from the spirit thereof.

I claim:

I. A projector lamp device comprising a cup shaped shell including a base wall having an opening therein and a forwardly directed peripheral skirt wall. a first plate disposed forwardly ofsaid shell base wall and having an opening therein registering with said base wall opening. a sleeve secured to said first plate in registry with the opening in said lirst plate and projecting rearwardly through said base wall opening. means supporting said first plate on said shell base wall for angular ad justmcnt of said first plate about angularly related axes, a lamp socket assembly disposed forwardly of said first plate and including a socket rear mounting plate. a spring member having a base section bearing on the front face of said first plate and having an opening registering with said first plate opening and a plurality of angularly spaced curved forwardly outwardly projecting leaf spring lingers extending from said base section into engagement with peripherally spaced points on said socket rear mounting plate. a screw member secured to said socket rear mounting plate and projecting rearwardly loosely through said sleeve and an adjustable nut engaging said screw member rcarwardly of said sleeve.

2. The device of claim 1 including a stop element located on the inside face of said skirt wall and a curved leaf spring extending from said spring member base section to said stop element to rearwardly urge said base section into bearing relationship on the front face of said first plate.

3. The device of claim 2 wherein said first plate ineludes an annular rearwardly. inwardly. direct lip surrounding the opening in said first plate and bearing on said shell rear wall.

4. The device of claim 3 wherein said shell base wall has a pair of peripherally spaced apertures equidistant from the opening in said shell base wall and pcriphcr ally spaced and said first plate has a pair of tapped openings angularly aligned with said shell base wall apertures and said first plate support means comprises screws projecting through said shell base wall apertures and engaging said first plate tapped openings.

5. The device of claim 1 including a forwardly concave reflector positioned forwardly of said lamp socket assembly and having a central opening coaxial with said lamp socket assembly.

6. A lamp position adjusting apparatus for use in a projector having an umbrella-shaped reflecting mirror comprising: a disc with a central hole and a portion around the central hole protruded into the configuration of a truncated cone or hub rising in one direc tion from the disc plane: a cup-shaped member (114) adapted to receive a lamp and having a projection on an inner surface; a tubular sleeve (l20bi having an inner end coaxially fixed in the central hole of said disc (120) and loosely inserted from the inside into a hole bored centrally in the bottom of said cup-shaped member I14); a lamp socket (107a) having a bottom wall; a bolt (H8) coaxially engaged with said lamp socket (107a) loosely inserted into said tubular sleeve from the inner end thereof; a nut (121) threaded onto the projected end of said bolt; a ring ([19) arranged between said disc 120) and lamp socket (107a) and having a central hole loosely penetrated by said bolt (118); a plurality of loop springs (119a). each extending integrally and radially from the circumference of the ring 1 19] in the form of arches rising unidirectionally from the ring plane and engaging the peripheral portion of said bottom wall of the lamp socket for thereby urging the same in the forward direction: another curved leaf spring (11%) extending integrally and radially from the curcumference of said ring (119) and having a free end engaging said projection formed on the inner wall surface of said cup-shaped member 114) for thereby making said hub portion or truncated conical portion of said disc (I20) pressedly engage with the inner bottom surface of said cup-shaped member 114); and two screws (122) loosely and externally inserted through 

1. A projector lamp device comprising a cup shaped shell including a base wall having an opening therein and a forwardly directed peripheral skirt wall, a first plate disposed forwardly of said shell base wall and having an opening therein registering with said base wall opening, a sleeve secured to said first plate in registry with the opening in said first plate and projecting rearwardly through said base wall opening, means supporting said first plate on said shell base wall for angular adjustment of said first plate about angularly related axes, a lamp socket assembly disposed forwardly of said first plate and including a socket rear mounting plate, a spring member having a base section bearing on the front face of said first plate and having an opening registering with said first plate opening and a plurality of angularly spaced curved forwardly outwardly projecting leaf spring fingers extending from said base section into engagement with peripherally spaced points on said socket rear mounting plate, a screw member secured to said socket rear mounting plate and projecting rearwardly loosely through said sleeve and an adjustable nut engaging said screw member rearwardly of said sleeve.
 2. The device of claim 1 including a stop element located on the inside face of said skirt wall and a curved leaf spring extending from said spring member base section to said stop element to rearwardly urge said base section into bearing relationship on the front face of said first plate.
 3. The device of claim 2 wherein said first plate includes an annular rearwardly, inwardly, direct lip surrounding the opening in said first plate and bearing on said shell rear wall.
 4. The device of claim 3 wherein said shell base wall has a pair of peripherally spaced apertures equidistant from the opening in said shell base wall and peripherally spaced 90* and said first plate has a pair of tapped openings angularly aligned with said shell base wall apertures and said first plate support means comprises screws projecting through said shell base wall apertures and engaging said first plate tapped openings.
 5. The device of claim 1 including a forwardly concave reflector positioned forwardly of said lamp socket assembly and having a central opening coaxial with said lamp socket assembly.
 6. A lamp position adjusting apparatus for use in a projector having an umbrella-shaped reflecting mirror comprising: a disc (120) with a central hole and a portion around the central hole protruded into the configuration of a truncated cone or hub rising in one direction from the disc plane; a cup-shaped member (114) adapted to receive a lamp and having a projection on an inner surface; a tubular sleeve (120b) having an inner end coaxially fixed in the central hole of said disc (120) and loosely inserted from the inside into a hole bored centrally in the bottom of said cup-shaped member (114); a lamp socket (107a) having a bottom wall; a bolt (118) coaxially engaged with said lamp socket (107a) loosely inserted into said tubular sleeve from the inner end thereof; a nut (121) threaded onto the projected end of said bolt; a ring (119) arranged between said disc (120) and lamp socket (107a) and having a central hole loosely penetrated by said bolt (118); a plurality of loop springs (119a), each extending integrally and radially from the circumference of the ring (119) in the form of arches rising unidirectionally from the ring plane and engaging the peripheral portion of said bottom wall of the lamp socket for thereby urging the same in the forward direction; another curved leaf spring (119b) extending integrally and radially from the curcumference of said ring (119) and having a free end engaging said projection formed on the inner wall surface of said cup-shaped member (114) for thereby making said hub portion or truncated conical portion of said disc (120) pressedly engage with the inner bottom surface of said cup-shaped member (114); and two screws (122) loosely and externally inserted through corresponding holes bored eccentrically in the bottom of said cup-shaped member at an equal distance from the center thereof and along two radii crossing at right angles and then threaded into corresponding eccentric holes (122a) bored in said disc (120). 